What is vector-borne disease?
A micro- or macroparasite transmitted among vertebrate hosts by an arthropod vector
Vector-borne diseases represent some of the deadliest, most impoverishing diseases of mankind and wildlife
A micro- or macroparasite transmitted among vertebrate hosts by an arthropod vector
Vector-borne diseases represent some of the deadliest, most impoverishing diseases of mankind and wildlife
Vectors are flying syringes
Host preference determines encounter
Huge economic cost
Some rough diseases
Vectors take blood or host tissue (including pathogen) and transmit to same (or different) species
Means reservoir hosts are really important
Eigenbrode & Gomulkiewicz 2022 J Economic Entomology
$12 billion per year (Chilakam et al. 2023 doi:10.2196/50985)
$100 billion economic costs per year (USDA-ARS report)
More important is the cost in terms of impacts to human and wildlife
“Keep their (Anopheles gambiae) DNA for future research and let them go” -EO Wilson
Fang 2010 Nature; and associated 4+ replies
Mosquitos
Ticks:
Other:
Yersinia pestis, a bacterial pathogen
Vectored by fleas
Killed 25% of Europe’s pop in 1300’s
Exists in enzootic cycles with transmission between rodents and fleas
Borrelia burgdorferi, a bacterial pathogen
Vectored by ticks (Ixodes scapularis as main vector)
Ancient disease (plagued humans prior to European Colonization)
Disappeared around 1850’s due to deforestation
Dengue (33%+ of world pop at risk)
Chikungunya (45 countries affected)
Zika (61 countries affected, 47 in Americas)
Malaria (kills ~1 million people per year)
Flores & O’Neill 2018 Nature Reviews Microbiology
Ainsworth 2023 Nature
Host and vector terms are both in there
We can look across probable parameter ranges to see the effect of each component
Is it more important to reduce vector infection probability ( \(b_v\) ) or host duration of infection ( \(1/r\) )
Hancock et al. 2018 PNAS
Vector-borne disease is pretty rough
We have a decent model of vector-borne disease
It can help identify suitable mitigation strategies
Mixed, but probably not
Important because:
Vector feeding preferences are particularly important for multi-host systems
Can introduce variation in exposure across different groups of individuals within a host population
Vector preference can inform intervention strategies based on vector and reservoir communities
Response to this (and other bat-vectored disease) is to try to kill bats
Often killed the wrong bats
Some efforts potentially increased disease in humans
https://www.reuters.com/investigates/section/global-pandemic-bats-overview/
Infected malaria mosquitoes prefer warmer environments
An example of host manipulation by the a pathogen?